viii PREFACE 



of new facts of importance for the general physiology of the 

 effects of stimulation have been obtained. All these results I 

 have endeavored to combine and elucidate in the following 

 lectures. 



The text of the lectures in its present form was written in 

 German in 1911. The English translation was made by my wife, 

 with the help of our friend, Dr. Lodholz of the University of 

 Pennsylvania, who also undertook the reading of the proofs. 

 We wish here to thank him once again and express our deep 

 appreciation of the great sacrifice of time and labor involved in 

 this task. I am likewise much indebted to Dr. Julius Veszi for 

 his assistance unstintingly given, especially in obtaining a number 

 of curves. Finally, I wish to take this opportunity to render 

 warmest thanks to the authorities of Yale University, and espe- 

 cially to President Hadley and Professor Chittenden, as well as 

 to my special colleagues, for the hospitality and cordial reception 

 extended to me in New Haven and for the pleasant hours I was 

 privileged to spend in their midst. 



Max Verworn. 



Bonn. 



Physiological Laboratory of the University. 



